Trying to jailbreak 3GS on iOs 6.0.1

Hello everybody. I have an iPhone 3GS my brother gave me, it was originally on O2 Ireland but I want to use in on O2 UK. I got it unlocked in a high-street shop and it worked fine but I could not download any of the newer apps as they all neded iOs 4.3. (it was installed with 4.1)

So I then went into iTunes and upgraded it to the latest iOS thus re-locking it. I then tried a myriad of programs including redsn0w, absinthe, blackrain, in an attempt to unlock it. no joy. Finally I gave up, I went to some high street stores and asked them if rthey could put iOs 4.3 or higher on it as I just wanted to use facebook etc. One guy told me it's impossible to put anything higher than 4.1 on that phone. Another shop said it's possible to put 5.1.1 on it but I didn't believe him.

So I still have the phone, locked and it's driving me crazy my current (android) phone is crap and keeps switching off. I'd really appreciate any help on this. To the best of my knowledge it's an iPhone 3GS and the baseband is 6.0.15 (at least it was...I have no way of checking it at the moment)

Can you recommend a good (cheap) hardware unlock? Does this mean I won't have to worry about upgrading the iOs in future? How is this achieved? Do I need any special hardware to perform a hardware unlock? Thanks, Nodgie